Katie Couric's Notebook: Older Facebookers

They are members of the fastest growing group on Facebook. Not teenagers, not college students but Grandma and Grandpa.

The percentage of internet users 65 and older who log onto social networking sites more than doubled in the past year from 13 to 26 percent. A recent study by the Pew Research Center shows 50-64-year-olds are right on their heels. Half of them now have profiles - an increase of 88 percent.

Sure, 18-to-29-year-olds are still the heaviest users of social media sites, but they've been posting comments, links and photos for years now. So, there hasn't been a lot of recent growth among younger users ... and many older Americans are only now catching up.

So, go ahead. See if Grandma's on Facebook and friend her.

But if she also has a scanner just make sure those embarrassing old photos of you stay safely in her scrapbook ... and not tagged for everyone to see.

That's a page from my notebook.

I'm Katie Couric, CBS News.